Assist device for sclerosing treatment of varicose veins

ABSTRACT

Assist device ( 10 ) for sclerosing treatment of varicose veins, aimed at being partially inserted into a blood vessel ( 20 ), including a tubular element ( 11 ), which has at least three ways ( 13, 14, 15 ), at least two of which ( 13, 14 ) are connected to at least one related inflatable balloon element ( 12, 12′, 16 ) by at least one through hole ( 30, 31 ), and at least one remaining way ( 15 ) of said three ways ( 13, 14, 15 ) has at least one hole ( 32 ) for the passage of a sclerosing substance ( 17 ), aimed at reaching a wall ( 18 ) of said blood vessel ( 20 ), in which at least one ( 16 ) of said at least two balloon elements ( 12, 12′, 16 ) has an elongated shape extending toward at least another balloon element ( 12, 12′ ) and a volume comprised in the range of 30% to 99% of the space inside said blood vessel.

FIELD OF THE INVENTION

The present invention relates to an assist device for sclerosingtreatment of varicose veins. In particular, the present inventionconcerns an intravascular catheter, which is introduced into the veinssuffering from varices, so as to assist a local sclerosing treatmentusing a liquid drug or sclerosing foams.

BACKGROUND OF THE INVENTION

One of the most frequent pathologies that affects the venous system ofthe Western population is represented by the venous insufficiency, andnowadays it is estimated that more than 60% of the adult populationsuffers from this problem.

The most common manifestation of this pathology is varix. This termindicates the dilation, the tortuous course of the superficial veins,the valve insufficiency with a related reflux, whose appearance ismainly referable to intrinsic anomalies of the vein wall, highintraluminal pressure, structural and functional vein changes.

Although varicose veins constitute a benign pathology, they can beaccompanied by two kinds of serious complications: ulceration andthrombophlebitis. The ulceration occurs usually near the ankle and,generally, in cases of particularly extended varices, while thethrombophlebitis consists of the presence of thrombi, real plugsconstituted initially by platelets and fibrin, to which red corpusclesare added later inside the vein, together with an inflammatory responseof the vein wall. The complication of the thrombophlebitis is pulmonaryembolism, that expresses itself with clinical pictures of differentseriousness, up to death.

The therapy for the varicose disease, proposed today, follows four kindsof approach: pharmacological, elastic compressive, surgical subdividedinto classical or endovascular and sclerotherapeutic.

In particular, the endovascular surgery has been recently standing out,because of its less invasive character, and the sclerotherapy, thatlives a new era with the arrival of the foams. The sclerotherapyconsists of injecting into the varix a sclerosing substance which causesthe lumen closure and consequently, disappearance of the varix, followedby application of an elastic compressive brace (stocking or bandage).This method is getting more and more attention from medicine.

Four variables must be taken into consideration, in order to make thesclerosis efficient:

1) the drug must have high destructive power on the endothelium andpossibly also on the subendothelial structures and at the same time begentle to other vasal and perivascular structures and further it shouldnot have significant systemic side effects

2) it must get in contact with as much of endothelial surface aspossible

3) the concentration of the drug must remain as stable as possible inthe injection place and/or in the place of contact with the vein wall,

4) the contact time must be sufficient to determine the damage. Atpresent, the sclerotherapy is commonly carried out by injecting asclerosing drug in liquid form, or a so-called sclerosing foam, apreparation, in which the active substance having foaming capability isfirst subjected to a turbulence by energetic shaking, that creates microbubbles (30-100 micron diameter) structured foam or mousse constitutedsubstantially by gas, internally, and by foam active substance, thatforms the outer surface of the bubble, for example of drug: sodiumtetradecilsulphate or polydocanol.

The diluting effect due to the circulation can be considered aconsequence on one hand positive, since it limits the risks of aprogressive and uncontrolled sclerosis, on the other hand negative,because the dilution influences the sclerosis efficacy.

The sclerosis with foam or mousse has overcome successfully the dilutionproblem: the mousse (micro-bubbles of gas and drug) does not mix with aliquid, and, once injected into vein, it is capable of displacing theblood and coming in contact with venous endothelium more easily,improving the sclerosing effect (a better immediate and distant resultappears from the literature). Therefore, it behaves as an almost solidsubstance and actually, it is a dynamic fluid aggregate of bubbles.

This has allowed reducing the dose of drug being used and itsconcentration (thus, we would expect a smaller number of complications,but actually the exact opposite effect appears from the literature: alarger number of side effects and new side effects).

Actually, it has been noted that the injected micro-bubbles get into thecirculation and are subjected to the venous circulation effect, which isextremely variable at the lower limbs level, due to the systemcomplexity, and moreover, it is difficult to predict its flowdirections. Therefore, the micro-bubbles can reach the deep venouscirculation, thrombosis of the deep veins, and inevitably, end up in thelung and the systemic circulation, thus causing side effects (headache,visual alterations, constriction in the chest), even potentially serious(stroke).

Consequently, in order to try to enhance the sclero-mousse methodologyefficacy, some devices have been conceived and produced, substantiallycatheters, which are capable of better controlling the sclerosing foamlocation, the contact time of the drug with the vein wall, its effectand possible side effects.

A first device of this kind is a direct catheter, which is used forinjecting the sclerosing foam at the desired point and along the wholevenous axis, during the catheter distal end withdrawal. With thiscatheter, it is possible to control the place and the quantity of theinjected drug (echo-sclerosis), however it is not possible to control aseries of events: 1) the dilution caused by the blood flow thatdisperses the bubbles 2) the effective contact of the drug with thewhole wall, for the same reason 3) the contact time, for the same reason4) getting into the circulation, for the same reason.

Currently, other typologies of catheters are known: a two-way catheterwith a distal balloon that allows to better control the sclerosing foaminjected into the vessel through outlet holes, situated near theballoon, holes that allow sucking the foam out of the vessel through thesame catheter afterwards. Another one, still with a distal balloon, buthaving many holes along the catheter axis, so as to distribute uniformlythe drug in the part of the vein to be treated.

Also these two catheters are not completely free from some limits. Thefirst device does not ensure a uniform concentration of the drug (foam)along the entire section of vessel to be sclerosed. The concentrationdecreases as one moves away from the balloon, that is from the outlethole. Consequently, the varicose vein treated section will get incontact with a more and more diluted drug (foam), as one moves away fromthe outlet hole. It is confirmed by the fact that during the foamsuction step, a mixture of foam/drug and blood is constantly recovered.

Moreover, because of the necessity to carefully inject quantities offoam not bigger than 6-10 cc, the initial volume of the varicose vein tobe treated can influence even considerably the drug/volume ratio insidethe vessel and in some cases jeopardize its therapeutic result.

In the second case, with more outlet holes, even if a more homogeneousconcentration can be maintained along the whole section of the vein, anda given quantity of drug (for example 8 ml) must be used, standardconcentrations of drug cannot be ensured in the section of the vein tobe treated, for all kinds of varices.

Thus, all these devices, some more some less, along with the vesselsubjected to a sclerosing therapy, constitute an “open system”, that isa system under the influence of the venous circulation, resolve onlypartially the previously described problems.

In order to obviate such disadvantages, one must take into considerationthe necessity to isolate the part of varix to be treated with a doubleballoon catheter, thus creating a “closed system”, not exposed to theeffect of the local venous circulation. Such a “closed system” iscomposed of the segment of varix under consideration, the catheterpresent therein, two balloons at the extremities, the blood contained inthe isolated and static section of the vein.

The drug, in the form of mousse (stable and constant volume), isinjected into such a “closed system”, dislocates, in the smallcollateral vessels, the blood contained in the system, occupying theentire part of the vein being treated without any dilution.

The characteristic feature of this system is the location of the foam ina closed system, which consequently is not subjected to the localcirculation effects, thus resolving the dilution problem.

However, although theoretically this system fulfills the conditions tobe considered stable and thus efficient, also such solution has somelimits.

Actually, the veins to be treated with the sclerosing foam can havevariable dimensions and volume, that can range from a minimum of about7-10 cm³ to a maximum of 90-120 cm³ and, since one cannot introduce asbig quantity of sclerosing foam as desired, so as not to make its effectuncontrollable, for example having to use about 8 ml of foam, to satisfythe treatment of a section of vessel, whose volume varies from 10 cm³ to100 cm³, it is noticed immediately that in the first case the foamconcentration and the volumetric filling of the part of the vein to betreated is high (8:10=80%), while in the second case it is very low(8:100=8%).

This causes a high foam-volume concentration in the first case and avery low one in the second case, with obviously very different finalresults.

Therefore, disadvantageously, the two-balloon catheters defining aclosed system do not allow treating efficaciously big dimensions bloodvessels without introducing big quantities of medicine and consequently,risking to lose the control over the treatment.

Moreover, since it is necessary to inject into a closed system with twoballoons at the ends, the syringe will require high operating pressure,so as to be able to dislodge the blood in the collateral vessels. Thiscould cause a leakage of the micro-bubbles into the collateralcirculation (perforating), before emptying the section of the part ofblood, thus increasing the TVP risk.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an assist device forsclerosing treatment of varicose veins, which is capable of resolvingthe above mentioned drawbacks of the known technique in an extremelysimple, economic and particularly functional way.

Another object of the present invention is to provide an assist devicefor the sclerosing treatment of varicose veins, that defines a closedsystem, which can allow an efficient and standardized treatment of thevarices using the sclerosing foams, ensuring an optimalfoam-volume-surface of the vessel to be treated ratio.

A further object is to provide an assist device for the sclerosingtreatment of varicose veins, that allows improving the sclerosing actionof the sclerosing mousse, reducing at the same time possible sideeffects related to the foams.

A still further object is to provide an assist device for the sclerosingtreatment of varicose veins, that allows using a low quantity ofsclerosing drug, also for blood vessels of big dimensions.

Yet a further object is to provide an assist device for the sclerosingtreatment of varicose veins, that allows using an action efficacy time,which is not affected by external agents capable of altering thesclerosis efficacy (closed system).

The above mentioned objects are obtained according to the presentinvention by a device (10) at least partially insertable into a bloodvessel (20) for assisting a sclerosing treatment of varicose veinscomprising a tubular element (11) having at least three ways (13, 14,15), at least two (13, 14) of said at least three ways each beingconnected to at least one related inflatable balloon element (12, 12′,16) by at least one through hole (30, 31), and at least one remainingway (15) of said three ways (12, 14, 15) has at least one hole (32) forthe passage of a sclerosing substance (17), for reaching a wall (18) ofsaid blood vessel (20), wherein at least one (16) of said balloonelements (12, 12′, 16) has an elongated shape extending toward at leastanother (12, 12′) of said balloon elements and a volume in a range from30% to 99% of the space inside said blood vessel (20), conveniently theat least one (16) of said balloon elements being interposed between theexternal surfaces of the outermost of said at least two balloon elements(12, 12′), so that said elongated balloon element (16), extending towardanother balloon element, standardizes the residual volume to be filledwith said sclerosing substance, independently from the dimensions of thevessel to be treated.

Other characteristics of the invention are pointed out in the dependentclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics and advantages of an assist device for sclerosingtreatment of varicose veins, according to the present invention willbecome clearer from the following description, given as a pure, notlimiting example, with reference to the enclosed schematic drawings, inwhich:

FIG. 1 shows an embodiment of an assist device for sclerosing treatmentof varicose veins, according to the invention, during an in-operationstep and inserted in a blood vessel; and

FIG. 2 is a schematic view, in vertical section, of a portion of thedevice of FIG. 1; and

FIG. 3 shows another embodiment of an assist device for sclerosingtreatment of varicose veins, according to the invention during anin-operation step and inserted in a blood vessel; and

FIG. 4 is a schematic view, in vertical section, of a portion of thedevice of FIG. 3;

FIG. 5 shows a further embodiment of an assist device for sclerosingtreatment of varicose veins, according to an in-operation step andinserted in a blood vessel; and

FIG. 6 shows a further embodiment of an assist device for sclerosingtreatment of varicose veins, according to the invention, during anin-operation step and inserted in a blood vessel.

BEST MODES OF CARRYING OUT THE INVENTION

With reference to the Figures, an embodiment of an assist device forsclerosing treatment of varicose veins, according to the invention isshown and indicated as a whole with reference numeral 10.

The shown device 10 is aimed at being partially inserted into a bloodvessel 20 and includes a tubular member 11, having at least three ways13, 14, 15.

The three ways 13, 14, 15 are independent one from another, and at leasttwo of them 13, 14 are connected, each by related through holes 30 and31, to at least one balloon element 12, 12′ and 16.

Advantageously, the provided embodiments of the device proposed by thepresent invention include at least two balloon elements 12, 12′ and 16.

Typically, at least two balloon elements 12, 12′ and 16 are inflatableand reach their maximum expansion when a fluid, typically a liquid suchas a normal saline solution, introduced into the related ways 13, 14 byan operator from outside, is conveyed into them through the abovementioned related through holes 30, 31.

Also the other at least a way 15 has at least one hole 32, in the regionof which there is no element, so that a substance, typically in solution17, inserted from outside into the related way 15, reaches the walls 18of the blood vessel 20.

Such a substance 17 contains a drug, such as polydocanol, for thesclerotherapy, that can be either a solution, or advantageously, foam.

In order to facilitate the insertion of the related substances into thethree ways 13, 14, 15, the device 10 includes also an adapter 21, inwhich the three ways can be reached separately and individually by anoperator from outside.

According to an embodiment. at least one balloon element 16 of the atleast two above mentioned balloon elements 12, 12′ and 16 has preferablya non symmetrical spherical shape, which typically is elongated towardat least one other balloon element 12, 12′, that usually has a sphericalshape.

According to an embodiment, the elongated balloon 16 has a fixedlongitudinal axis, that cannot be changed, and a transversal section,that can be changed, due to the inflation effect.

According to an embodiment of the invention, the inflated balloonelement 16 occupies almost the whole space of the vessel interposedbetween the two of at least two balloon elements 12, 12′ and 16, whichare situated at the end of the device 10.

In this way, after having been inflated and dislocated the blood, theelongated balloon element 16 occupies between 30% and 99%, preferablybetween 60% and 80% of the inner space of the blood vessel 20 to betreated, interposed between the external surfaces of two of the at leasttwo balloon elements 12, 12′ and 16, which are situated at the end ofthe device 10.

Typically, since the elongated balloon 16 can change its dimension, notin longitudinal direction, but substantially only in the transversalone, that is, it can change its diameter due to the inflation, it iscapable of changing, reducing its volume, the quantity of blood presentin the part of vein to be sclerosed. Depending on the inflation degree,the balloon can empty the part of varix to be treated substantially(about 99%) or only partially 60-80%. Therefore, independently from theinitial dimensions, diameter/volume, of the vessel to be treated, thatcan widely vary from 10 cc to 120 cc, and due to the volumetricmodularity of the elongated balloon, interposed between at least twospherical balloon elements 12 and 12′, it is possible to create always astandard residual volume of the blood vessel to be sclerosed. Typically,such residual volume of a vessel full of blood, will be restricted inthe area comprised between

A) the at least two spherical balloons 12 and 12′;

B) the at least one elongated balloon 16, coaxial with the catheter and

C) the wall 18 of the blood vessel 20.

Advantageously, the drug is then injected in such residual volume. Ifthe residual volume of the vein is standard, independently from theinitial volume, the quantity of drug to be used must be always the same,independently from the vessel initial volume. The use of always the samequantity of drug in a closed system means standardization of thetreatment.

According to this embodiment, the standardization is possible becauseall the negative variables can be controlled: 1) the dilution caused bythe blood flow, 2) the contact time depending on the flow; 3) thecontact with all the endothelium along its whole circumference; 4) thedrug concentration in the residual volume for the reasons explainedbefore. Generally, the tubular element 11 is made of radiopaquepolyurethane or Pebax, incompressible and flexible, while the balloonelements 12, 12′ and 16 are made of latex, covered or not, withpolytetrafluoroethylene (PTFE), of silicone, or other elastic material.

As already said beforehand, the assist device for sclerosing treatmentof varicose veins, according to the invention, has at least two balloonelements 12, 12′ and 16, at least one of which 16 is preferablyextendable. Thus, according to preferential embodiments, there can beembodiments that include a number of balloon elements bigger than, equalto, but never smaller than two, as shown in FIGS. 1 and 2.

Otherwise, it is possible to have more, for example three balloonelements, as shown in FIG. 3.

According to the embodiment with two balloon elements 12 and 16, shownin FIGS. 1 and 2, after having been inflated, the balloon element 16occupies almost the whole space interposed between the latter and theremaining balloon element 12.

In particular, the inflated balloon element 16 occupies from 30% to 99%,preferably from 60% to 80%, of the inner space of the blood vessel 20 tobe treated, interposed between the external surfaces of the two balloonelements 12, 16.

Consequently, according to this embodiment, the balloon element 16 has anon symmetrical shape, including a portion elongated toward said balloonelement 12, which begins from an approximately spherical portion.

A contact between the wall 18 of the blood vessel 20 and the balloonelement 16, in this example, occurs only in its spherical portion, whichis located in a position opposite to the other balloon element 12.

According to an embodiment, the inflatable balloon element (16) includesan elongated portion which permits first the inflation of the sphericalportion and after of the cylindrical portion extending toward saidballoon element (12).

According to an embodiment, the balloon (16, 12, 12′) of the device ofthe invention can be made of an (elastically) deformable material havingdifferent stiffness/wall density or of two or more materials havingdifferent elastic properties in order to permit sequential inflation anddeflation of portions thereof. For example, when the balloon 16 is madeof a single elastic material, it is possible to have the sphericalportion of the balloon 16 with a lower thickness or material densitythan the elongated portion. In this way, the differential walldensity/thickness of the material of the balloon 16 allows a sequentialinflation and a subsequent deflation steps. In particular thisembodiment enables the operator to inflate first the spherical part ofthe balloon 16 (which is thinner) and afterwards the elongatedcylindrical part.

Typically, such effect of sequential expansion of the elongated balloon16 could be obtained also by using two materials having differentstiffness for the spherical part and the elongated cylindrical part,forming the balloon. Otherwise, the same effect could be achieved by anembodiment with a balloon molded with such shape, elongated with one ofthe two ends being spherical (FIGS. 1 and 2).

According to a further embodiment, there are more than two balloonelements and, as shown in FIG. 3, there can be for example three balloonelements 12, 12′ and 16.

At least one balloon element 16 of these three balloon elements 12, 12′and 16 has an elongated form and preferably it is the one situated in acentral position between the other two 12, 12′.

Typically, the balloon element 16 has an elongated form, is interposedbetween the two spherical balloons 12 and 12′, placed externally and,once inflated, it occupies from 30% to 99%, preferably from 60% to 80%,of the inner space of the blood vessel 20 to be subjected to thesclerotherapeutic treatment.

According to this embodiment, the elongated balloon element 16 has asymmetric form with two external elongated portions extending, beginningfrom a central spherical portion, toward the remaining two balloonelements 12, 12′.

According to this embodiment, there can be a balloon 16 with elongatedshape, as described above, such that it gets in touch with the wall 18of the blood vessel 20 in its central portion, FIG. 3, and in this case,forming two closed systems, there are holes 32 in both said systems, orthere can be a central balloon 16 with elongated shape, that does notget in touch with the wall 18 of the blood vessel 20 in any point.

In the last case, a single closed system is created, delimited by theremaining two lateral balloon elements 12 and 12′, FIG. 5, and there canbe even only one hole 32.

In this way, the same effects of the embodiment shown in FIGS. 1 and 2with two balloon elements 12 and 15, are ensured.

In the just described embodiment with three balloon elements, taking thecentral one as the elongated element, being symmetrical, it is possibleproviding, without jeopardizing the device efficacy, a uniform walldensity of the material, from which the device has been made, or onlyone material for the whole elongated balloon element 16.

Finally, the elongated balloon element 16 works typically in anautonomous way with respect to other remaining balloon elements.

This is allowed in all the embodiments by providing that one of the atleast three ways 13, 14, 15, present in the device 10, is aimed,exclusively and independently from the remaining two, at supplying theelongated balloon 16.

The remaining ways of the at least three ways 13, 14, 15, will supply,always independently, the drug to the treated part of the vessel and theother balloon elements 12, 12′.

It is quite easy to understand the operation of the device proposed bythe invention.

The device 10 belongs to the category of catheters for sclerosingtreatments, which are capable of creating a closed and isolated system,in the area of the blood vessel subjected to the treatment.

Typically, in the operative conditions the catheter is inserted in ablood vessel to be treated. After the insertion, the balloon element 16including an elongated portion, typically having a substantiallycylindrical shape, is inflated by means of the passageway 14 and thehole 31 in order to substantially fill the vessel to be treated bydislocating the blood therein contained, independently from the startingdiameter/dimension of said vessel. The next step comprises the inflationof the distal balloon 12 through the passageway 13 and the hole 30 insuch a way to substantially occlude the system (closed system). Afterthat, a sclerosing drug is injected by means of the passageway 15 andthe hole 32 to substantially fill the residual space existing betweenthe balloon 16 provided with the elongated portion and the second(distal) balloon 12. According to an embodiment, the elongated portionof the balloon 16 is partially deflated by means of the hole 31 and thepassageway 14, during drug injection. By this operation it is created adepression which make easier to fill the space in the middle of the wall18, the vessel 20, the balloon 16 and the second balloon 12.

Such closed system arrangement is indeed obtained by the presence of atleast two inflatable balloons 12, 12′ and 16, which, by expanding,isolate the volume of blood present therebetween from the bloodcirculation.

Further, according to an embodiment of the invention, at least one 16 ofthe said at least two spherical balloons 12, 12′ and 16 has an elongatedshape toward the at least another balloon element 12, 12′.

In this way, it occupies a volume in the range from 30% to 99% of thespace of the blood vessel interposed between the two balloon elements ofthe at least two ones 12, 12′ and 16, placed externally.

In this configuration, the free space remaining in such closed system ismuch smaller than the total volume of the blood vessel interposedbetween said at least two balloon elements, if such a devise was notpresent.

Moreover, such device is capable of reducing the above mentioned volume,so as to create a residual volume substantially standard, independentlyfrom the initial volume of the blood vessel to be treated. This effectis made possible due to the modularity of the elongated balloon element16, which can be expanded by few millimeters, e.g. 3-4 mm, in the veinsof small size, up to some tens, e.g. 20 mm and more, into the veins ofbig size.

In this way, by introducing even small quantities of drug 17, it ispossible to achieve an optimal medicine-volume-endothelial surface ofthe vessel 20 to be treated ratio, also in the cases when vessels of bigdimensions are to be treated.

Advantageously, the volumetric modularity of the balloon 16 allowsreducing the inner volume, thus standardizing the residual volume,volume that is to be filled with the drug, independently from theinitial diameter/volume of the vessel (e.g. 5-6 mm of diameter and 10-15cc or 15-16 mm of diameter and 90-100 cc).

Without the use of the device according to the invention, the bigvessels would require a big quantity of drug 17 to obtain the same rvolume/drug ratio, with the risk of losing control over the treatment.

Advantageously, in the embodiments described in the present explanation,both the one with three balloon elements 12, 12′ and 16, and the onewith two elements 12 and 16, the elongated balloon 16, lateral orcentral, as the case may be, as already said before, works in anautonomous way with respect to the others, with the provision of anindependent supply way for it.

The two remaining ways supply the remaining balloon elements 12, 12′ andthe drug 17 to the section of the vessel 20, subjected to the treatment.

In this way, the device with two balloon elements 12 and 16 has aballoon 12 dedicated supply way and another dedicated way for theelongated balloon 16, which will ensure, in operation, a sequentialinflation-deflation due to its wall different density.

First, the spherical part will be inflated, and then the elongated part,so as to dislodge the blood and, after inflation of the remainingspherical balloon element 12, it will be afterwards slightly reduced inits elongated part.

By acting in this way, a facilitated supply of the drug 17 into thecentral chamber would be allowed, due to return vacuum effect, caused bythe deflation of the elongated part of the balloon 16 (a smalldeflation, as the spherical-elongated balloon element 16 remains almostcompletely inflated). In case one decides to use a device with threeballoons 12, 12′ and 16, according to what said above, there will be oneway for the central elongated cylindrical balloon 16, and another wayfor the two lateral spherical balloons 12 and 12′.

In this way, the elongated balloon element 16 could be inflated first,to dislodge the blood and afterwards deflated a little, prior to thecontemporary inflation of the remaining spherical balloon elements 12and 12′.

The so conceived system constitutes an efficient “closed system”, whichcan be used in a “static or dynamic” way. Indeed, the described deviceaccording to the invention can operate in a static way, that is, onesets the device in place, then fills the chamber with the liquid or foamdrug 17 and waits the necessary effect time with the catheter motionlessin place (only afterwards the drug is sucked, the balloons are deflatedand the device is removed).

Otherwise, the device can operate in a dynamic way, that is, one setsthe device in place, then fills the chamber with the liquid medicine 17or foam and proceeds by temporal intervals, subsequent to progressiveremoval of the device along the whole varicous venous axis to betreated. This solution constitutes a “dynamic closed system”, because itis the chamber containing the drug that moves in the vessel, thusfacilitating drug contact with the whole vessel to be treated. Thesystem compares with the LASER o RADIOFREQUENCY treatments.

This therapy method uses catheters that carry heat energy, released intothe vessel through the head (the catheter tip) during the withdrawalstep, thus determining an endothelial damage with subsequent vesselsclerosis.

The “dynamic closed system” uses chemical energy (drug/sclerosingsubstance), that acts on the vein wall, determining the damage duringthe withdrawal step.

The “system is closed”, not modifiable, with a constant concentration ofdrug in the chamber, and consequently on the vein wall.

It is the system stability that standardizes the therapy, optimizing it,for vessels of any dimension.

It is the correct and constant concentration of the drug on the vesselwall that determines the maximum effect.

Naturally, from the realization point of view, devices of variousdimensions and proportions are provided.

For a same length of the vein section to be treated, the device can havedimensions comparable to the vein section, for example FIG. 1, and inthis case it will be used advantageously in “static” way, or, havingsmaller dimensions, FIG. 6, it can be used in “dynamic” way.

1-14. (canceled)
 15. A method for the sclerosing treatment of a bloodvessel, comprising: dislocating blood contained in a segment of theblood vessel by occluding the segment of the blood vessel with at leasttwo inflatable balloons; and injecting a sclerosing drug into thesegment of blood vessel to contact with the blood vessel's endotheliumalong its whole circumference.
 16. A method for the sclerosing treatmentof a blood vessel, comprising: providing a catheter comprising at leasttwo inflatable balloons, said at least two inflatable balloonscomprising an elongated inflatable balloon, said at least two inflatableballoons being connected through a tubular element and being inflatableand/or deflatable through said tubular element; inserting the catheterin a blood vessel to be treated; inflating said elongated inflatableballoon through said tubular element in order to dislocate the bloodcontained therein; inflating the remaining inflatable balloon orballoons of said at least two inflatable balloons through said tubularelement to occlude a portion of said blood vessel along a lengthsubstantially defined by said at least two inflatable balloons; andinjecting a sclerosing drug into the blood vessel through said tubularelement to substantially fill the residual space existing between theelongated balloon and the second balloon.
 17. The method of claim 16wherein the elongated balloon element is inflated so as to occupy from30% to 99% of the space of the blood vessel interposed between the twoballoon elements.
 18. The method of claim 16, further comprisingsuctioning the drug from the blood vessel through said tubular member;and removing the catheter from the blood vessel.
 19. The method of claim16, further comprising deflating said elongated inflatable balloonthrough said tubular element while injecting said drug into the bloodvessel through said tubular element.
 20. The method of claim 16, whereinsaid tubular element comprises: a first fluidic passage for inflationand/or deflation of said elongated inflatable balloon; a second fluidicpassage for inflation and/or deflation of the remaining inflatableballoon or balloons of said at least two inflatable balloons; and athird fluidic passage for injection of the drug into the blood vessel.21. The method of claim 16, wherein the portion of the blood vessel tobe occluded and treated through the catheter varies in time throughmovement of the catheter inside the blood vessel during treatment. 22.The method of claim 16, wherein after having filled in the residualspace existing between the elongated balloon and the second balloon withthe sclerosing drug, the catheter is moved along the blood vessel, thusfacilitating drug contact with the whole blood vessel to be treated.